程海微囊藻毒素的结构分析

STRUCTURAL ELUCIDATION OF TOXINS FROM MICROCY- STIN AERUGINOSA COLLECTED IN CHENGHAI LAKE

从中国云南程海湖获得的“水华”藻类样品中分离很到具有肝毒性的微囊藻毒素，用ＮＭＲ，ＭＳ等多种结构分析手段鉴定，证明主毒素是一种环状七肽，含有Ａｄｄａ，β－Ｍａｓｐ，Ｍｄｈａ和ＧＬｕ各一分子以及２个Ａｒｇ残基．相对分子质量１０３８即为Ｍｉｃｒｏｃｙｓｔｉｎ－ＲＲ．进一步利用二维核磁共振技术测定发现此毒素有两部分，它们是冈分异构休，区别仅在于Ａｄｄａ上的２个双键的构型差异．

The Microcystin aeruginosa toxin which is lethally toxic was isolated from“water-bloom”sample obtained from Chenghai Lake in Yunnan Province,China.NMR,MS and other structural analysis methods were used to characte- rize the structure of the toxin.It was found that the toxin is cyclic peptide which contain one Adda,β-Masp,Ala,Mdha,Glu and two Arg amino acid resi- dues,and its molecular weight is 1038. It was proved that the toxin was Mic- rocystin-RR which has been reported in the literature.Investigation on the toxin by 2D NMR method found that the toxin was composed by two compo- nents,and the only difference between the two components is that the confor- mations of the Adda residues are different.